Heat exchange structure



June 26, 1956 J. DEDO 2,752,128

HEAT EXCHANGE STRUCTURE Filed Oct. 17, 1955 United States Patent HEAT EXCHANGE srnucrunn Lewis Joseph Dede, Racine, Wis, assignor to Mcdine Manufacturing Company, Racine, Wis, a corporation of Wisconsin Application October 17, 1955, Serial No. 540,837

7 Claims. (Cl. 257246) The invention relates generally to heat exchange structures and more particularly to a structure which may be utilized for the water cooling of oil, as for example, in connection with the cooling of oil in automatic transmissions in torque converters for vehicles and the like.

Oil coolers of the type referred to are subjected to high pressures and temperatures and structures of this type must therefore be manufactured to close tolerances and fits of formed parts to insure effective bonding capable of withstanding pressures involved at operational temperatures. High temperature bonding methods and the corrosive action of the water necessarily limit the choice of metals or alloys that may be used in such type of cooler. in the past, conventional coolers for this purpose have generally utilized cooling elements made of two flat metal sheets or plates between which is placed a suitable metal grid in effect forming a more or less fiat tube through which the oil flows.

The present invention therefore has among its objects the production of a heat exchange structure which may be utilized for the above purposes, which is extremely simple in construction, of maximum compactness and minimum weight.

Another object of the invention is the production or such a heat exchange structure which provides an inherently eflicient pressure retaining structure wherein the bond between any internal elements and the primary heat exchange surface for the purpose of producing turbulence as well as extended surface are not called upon to resist stresses due to high pressures in the oil cooler elements.

Another object of the invention is the production of such a heat exchange structure which may be readily designed for assembly in a fluid conduit, for exam ple, in a radiator hose line utilizing either flexible hose or other metallic or non-metallic conduit.

A further object of the invention is the production of such a heat exchange structure which may utilize a concentric arrangement of elements and in which several suitably designed elements may be arranged either for series or parallel fluid flow therethrough.

Many other objects and advantages of the construction herein shown and described will be obvious to those skilled in the art from the disclosure herein given.

To this end my invention consists in the novel construction, arrangement and combination of parts herein shown and described, and more particularly pointed out in the claims.

In the drawings, wherein like characters indicate like or corresponding parts:

Fig. 1 is a longitudinal sectional view through a fluid conduit having a cooler unit constructed in accordance with the present invention mounted therein;

Fig. 2 is a sectional view taken approximately on the line 2-2 of Fig. 1;

Fig. 3 is a greatly magnified perspective view of a portion of the grid structure utilized in the construction illustrated in Figs. 1 and 2; and

2,752,128 Patented .iune 26, 1956 Fig. 4 is a sectional view similar to Fig. 2 illustrating a construction adapted to be inserted into a hose or the like, this figure also illustrating the use of a pair of cooler elements concentrically arranged and connected in parallel.

Referring to the drawings and particularly Figs. 1, 2 and 3, the reference numeral 1 indicates generally a cooler element constructed in accordance with the invention, concentrically arranged in a fluid conduit 2 illustrated as being of rigid material such as metal, plastic or the like. The embodiment of the invention illustrated comprises inner and outer concentric cylindrical tubes 3 and forming an annular shaped passageway 5 therebetween, the ends of such passageway being suitably closed. In Fig. 1, the left hand end is illustrated as by being closed by suitably forming the free end of the tube 4 inwardly, whereby the extreme end portion ti thereof has int-= nal diameter substantially equal to the external diameter of the tube 3, the contacting portions be g suitably united to form a fluid tight joint. The right hand end of the element illustrated in Pig. 1 discloses an alternative closure of the passageway S, in which construction the end portions of the tubes remain unformed and an annular sealing ring 7 is inserted between the end portions of the tubes and suitably united therewith in fluid tight relationship. Obviously, if desired, instead or" one tube being suitably formed to provide an integral closure member thereon, both tubes could be partially formed whereby each tube provides a portion of the closure.

In the embodiment illustrated in l, ":e t is formed with two longitudinally aligned, circumferential openings 8 and 9 therein, one of which may function as an inlet and the other an outlet for the passageway 5. The openings 8 and 9 are defined by outwardly extending annular flanges 11, each being positioned in a counterbore 12 of a generally cylindrical connector and supporting member 13 having a threaded bore for the reception of suitable connection fittings. cc..- necting members 13 may extend through openings 15 in the conduit 2 and may be suitably secured thereto in fluid-tight relationship.

Positioned in the passageway 5 is a grid indicated by the numeral 16 which will hereinafter be termed the turbulator. As illustrated in Fig. 2, the tutbulator 16 may be fabricated in two halves 16a and 156/), each or. which may be formed from a single piece of material. Referring to Fig. 3, the member 16 may be formed by slitting the sheet material comprising the sme to form groups of parallel slits, each group being pr oncd on an axis extending parallel to the axes of other groups and corresponding slits in each group being aligned. The material between each pair of adjacent slits in a group may then be alternately positioned at opposite sides of the original plane of the sheet to form generally U-shaped portions 17a and 17b disposed at opposite sides of the sheet, the portions 17 of one group being connected to the portions 17 of the adjacent group by respective connecting strips 18, the latter extending parallel to one another as illustrated in Fig. 3. In the construction in Fig. 3, the portions 17a and 17b comprise side portions 19 connected by the top and bottom portions 2i, thus forming a series of more or less hexagonally-shaped structures when viewed from the ends of the connecting strips 18, and as viewed in Fig. 1.

As the structure thus formed embodies aligned planar connecting strips 18, forming the connections between adjacent groups, the corresponding members 17b of ti e respective groups are similarly positioned with their end edges lying in common planes. As a result of this arrangement, the structure illustrated in Fig. 3 may be bent into arcuate shape, the axis of curvature extending either parallel to the connecting strips 18 or parallel to the plane of the end edges of the portions 17a or 171;. In the construction illustrated in Fig. l, the turbulator structure 16 is bent into arcuate form on an axis extending parallel to the plane of the end edges of the portions 17a and 17b so that the walls B thereof are positioned transverse to the direction of flow through the passageway 5. This construction directs the, oil flow so that it will impinge on the primary surface of the cooler and create an undulating action which wipes away the oil film, thereby increasing the heat transfer by minimizing the oil film resistance to heat flow.

The construction thus enables the utilization of the turbulator or fin structure either as illustrated or with the end edges of the portion 17 facing the direction of flow which may be desirable in particular applications. The construction also facilitates the use of either me chanical or hydraulic means for expanding the inner tube following assembly to lock the turbulator and tube surfaces into intimate contact without necessitating the use of special jigs or fixtures to hold the parts in assembled relation, thereby providing optimum conditions for further bonding operations thereof if deemed desirable. It will also be appreciated that the present invention enables the use of simple manufacturing procedures employing standard materials of commercial tolerances in the component parts, and enables the use of integrally formed closure structures at the ends of the element as illustrated in the left hand end of the element as viewed in Fig. l, which construction I normally prefer to employ at both ends of the structure.

The invention also readily adapts itself for insertion into flexible fluid lines such as hose and also may utilize a plurality of elements arranged for either series or parallel flow therethrough.

Fig. 4 illustrates an embodiment of both such construe tions, in which the connecting member 13' is formed with a flange 22 having a curvature complemental to the inner face 23 of a flexible hose 24, the free end of the flange 22 being provided, if desired, with an outwardly extending sealing bead 25. Cooperable with the member 13 is a washer or collar 26 having an inner face complemental to the outer surface of the hose 24, the latter being clamped between the flange 22 and the collar 26 by means of a nut 27 threaded on the exposed end of the member 13'. The general construction of the cooler element 1 is similar to that illustrated in Figs. 1 and 2, with the member 4 secured to the member 13 in the same manner as previously described. Positioned within the cylindrical member 3' is a second cooler element indicated generally by the numeral 1a having inner and outer cylindrical members 3a and 4a. In the embodiment of the invention shown in Fig. 4 the elements 1 and 1a are illustrated as being connected together in parallel, the inner member 3 of the element 1 being formed with an opening 28 having a peripheral flange 29, the opening 28 being axially aligned with a similar opening 31 formed in the outer member 4a of the element in. The opening 31 likewise is defined by a peripheral flange 32. The flanges 29 and 32 may be positioned within a sleeve 33 and the entire assembly suitably formed together'to form an integral fluid-tight structure. The opposite end of the structure illustrated in Pig. 4 may be constructed in the same manner, whereby fluid may pass through the two elements 1a and I in parallel relation. Both of the elements 1' and 1a may be provided with turbulator grids 16' of a size and curvature to be positioned within their respective elements in the same manner as previously described in connection with Figs. 1 and 2.

If it is desired to connect the elements It: and l for series operation, the construction would be similar to that described, one end, however, of the structure being provided with an inlet directly into the inner element 1a, as for example, utilizing a construction similar-to that illustrated in Fig. 4 but providing a tubular member 34, indicated in dotted lines in Fig. 4, to seal the adjacent end of the inner element from the associated end of the outer element. The latter would then be provided with a seccond connection at such end of the device, which would be substantially the same as that illustrated in Figs. 1 and 4, so that such connection merely communicates with the adjacent end of the outer element, the latter preferably being extended to permit such connection to be longitudinally spaced from the adjacent connection into the inner element or may be positioned at the opposite side of the connection to the inner element. The opposite end of the structure may be constructed as illustrated in Fig. 4, a suitable plug being threaded into the connection 13 to operatively close the connection from the exterior whereby fluid may flow through the connection between the inner and outer elements. Thus, fluid will be admitted into one end of one of the elements, pass through the latter to the opposite end thereof, through the communicating port into the adjacent end of the other element, through the latter and out the connection at the opposite end thereof.

It will be noted from the above description that I have provided a cooler element which is exceedingly simple in construction and which may be readily installed in a fluid line to provide a very eificient heat exchange structure, particularly for oil cooler applications.

It will also be noted that the physical structure of the present invention is such that comparatively simple fabri cation techniques may be employed, utilizing components of generally standard construction such as tubing, etc., and at the same time produce a device which will Withstand the operating temperatures and pressures involved.

Having thus described my invention, it is obvious that various immaterial modifications may be made in the same without departing from the spirit of my invention; hence, I do not wish to be understood as limiting myself to the exact form, construction, arrangement and combination of parts herein shown and described, or uses mentioned.

What I claim as new and desire to secure by Letters Patent is:

1. A heat exchange structure for operatively mounting within a fluid passage so as to permit said fluid to flow through the heat exchange structure and therearound, said heat exchange structure comprising a pair of cooperable tubular members, one positioned in the other and forming a fluid passage therebetween, means for closing the ends of the passage so formed providing a passage for the fluid therethrough, an intermediate turbulator structure interposed between said tubular members, and extending across said fluid passage in heat transfer engagement with the adjacent side walls of said tubular members, said intermediate structure being formed from sheet material which is slit along groups of parallel co-extensive lines with such groups being arranged on parallel axes and corresponding lines of different groups being aligned, the material between adjacent slits of a group being disposed out of the plane of the sheet material alternately at opposite sides thereof and corresponding portions of adjacent groups being alternately disposed at opposite sides of the sheet material providing parallel extending and undulating substantially U-shaped strip fins aflixed together intermediate the slits of the contiguous groups, said turbulator structure being bent intermediate said groups to impart a shape to the structure corresponding to the shape of said passageway, and means associated with the outer member adapted to operatively connect said passageway in a fluid line and form supporting means for the heat exchange structure.

2. A heat exchange structure as set forth in claim 1, wherein said contiguous parallel extending and undulating substantially U-shaped strip fins provide a series of substantially hexagonal-shaped structures when viewed transverse to the direction of undulation.

3. A heat exchange structure as set forth in claim 1, wherein said turbulator structure is bent intermediate said groups to impart a substantially arcuate cross-sectional shape to the turbulator structure corresponding to the shape of the aforesaid fluid passage provided by the cooperable tubular members.

4. A heat exchange structure as set forth in claim 1, wherein said groups of the turbulator structure extend in the same direction as the axes of said tubular members, in radial spaced relation.

5. A heat exchange structure as set forth in claim 1, wherein said groups of said turbulator structure extend circumferentially in axial spaced relation with respect to the axis of the cooperable tubular members.

6. A heat exchange structure as set forth in claim 1, wherein said turbulator structure is provided by a plurality of similarly formed members completing the cross-sectional shape of the fluid passage provided by the cooperable tubular members.

7. A heat exchange structure as set forth in claim 1 6 adapted for operatively mounting within a fluid conduit for the coolant fluid, comprising means passing through said fluid conduit adapted to operatively connect the fluid passage between the cooperable tubular members and providing supporting means for the heat exchange structure.

References Cited in the file of this patent UNITED STATES PATENTS 1,840,318 Horvath Jan. 12, 1932 1,854,619 Mortensen Apr. 19, 1932 1,899,080 Valgliesh Feb. 28, 1933 1,903,387 Howe Apr. 4, 1933 1,983,466 Kline Dec. 4, 1934 2,135,235 Hurford et al Nov. 1, 1938 2,185,484 Welch et al Ian. 2, 1940 2,360,123 Gerstung et al. Oct. 10, 1944 

